It's a classic conflict: Developers focused on a project and facing deadline pressure want to use a lightweight enterprise service bus (ESB), while enterprise architects have to look at the long-term impact on the service-oriented architecture (SOA) environment.
However, the two sides do not have to come to grief if architects ask the right questions about the lightweight ESB, according to analysts at Forrester Research Inc. A new Forrester report with the hopeful title "Learn How To Embrace Lightweight ESBs: Lightweight ESBs Should Be An Option Within Your SOA Strategy," suggests a way for both sides to get what they want.
The conflict arises out of the desire of developers to find a simple solution, which makes the lightweight ESB seem an attractive alternative to more heavyweight versions, explain the report authors, Forrester analysts Mike Gilpin and Larry Fulton. In a one-off project, a lightweight ESB is easier to install and configure and provides enough functionality to get the job at hand done.
Typically, lightweight ESBs can be installed in a day, while full-feature ESBs can take weeks or even months to put in place, the authors note. For coders working on a deadline project, the choice is pretty simple. And it doesn't hurt that lightweight ESBs are -- not surprisingly -- less expensive than they heavy-duty counterparts, so they fit nicely into tight budgets.
However, for architects responsible for the overall SOA environment, there are legitimate concerns that less than full functionality will come back to haunt them. Will the lightweight ESB support the governance and interoperability requirements of the larger SOA environment? That is a valid concern, the Forrester analysts say, but they caution architects not to reject simplicity in favor of complexity out of hand.
As the Forrester report's title suggests, architects can learn to love, or at least embrace, the lightweight ESB as long as they make sure they are not buying a pig in a poke.
To make an informed decision on buying a lightweight ESB, the Forrester analysts suggest that architects get answers to some "tough" questions of vendors offering lightweight versions of their ESB:
- "Does the lightweight ESB integrate smoothly across the vendor's portfolio?" The issue here is that a lightweight ESB should share security, registry, governance and ESB metadata with its heavyweight brothers in the user's portfolio. Also, it should not require special integration to work with the user's other ESB products.
- "Are developer tools and skills transferable across the ESB portfolio?" Developers should not have to learn new tools when they move from working with a lightweight ESB to a more fully-functional one.
- "Does the vendor offer comparable service and support for all of its ESBs?" The lightweight ESB should be "a first-class citizen" when it comes to service and maintenance. Although the Forrester analysts note that there may be exceptions when dealing with an open source license, but they say it is a "key advantage" if a vendor offers consistent support for open source and commercial products.
- "Is a clear upgrade path available where needed?" If a more fully-functional version of the ESB is needed later, the Forrester analysts say: "Vendors should offer an attractive upgrade path to high-end options that preserve the initial investments made by customers in lightweight ESBs. Also, it is unacceptable to lose and have to rebuild key assets like configuration metadata — these should be smoothly transitioned."
If the answers to these questions are acceptable, then the architect can embrace the developers desire for simplicity, the Forrester analysts say.